Polymer optical waveguide devices play a key role in several rapidly developing areas of broadband communications, such as optical networking, metropolitan/access communications, and computing systems due to their easier processing and integration over inorganic counterparts. Because optical waveguide-based devices play a key role in communication systems that require signals to be processed optically at an ultrahigh speed, a low-cost material system and fabrication process suitable for mass production are desired to reduce the cost of integration. Fabrication and replication of polymer optical waveguides can involve several different processes such as embossing. An existing embossing process requires simultaneous application of ultraviolet (“UV”) radiation, pressure, and heat, which means that certain mechanical components and the mold must be UV transparent. Such a requirement is difficult to achieve in practice and can be incompatible with existing printed circuit board (“PCB”) production facilities.
Another deficiency of existing embossing is the generation of air bubbles during embossing. When the mold is pressed onto the polymer coated substrate, air bubbles can become trapped between the substrate and the mold. To eliminate air bubbles, vacuum treatment is usually used, which adds considerable complexity and expense to the process; sometimes, it may not even be possible to eliminate the air bubbles by vacuum treatment. Although special injected molding machines allow simultaneous application of UV radiation, pressure, and heat, these machines are complicated, expensive to build, and offer limited plate areas.
This background relating to fabrication and replication of polymer optical waveguides is merely intended to provide a contextual overview of some current optical waveguide fabrication technology, and is not intended to be exhaustive. Other context regarding current state may become apparent upon review of the following detailed description.